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At least 19 recordsLinked to original sources

Establishment and characterization of leukemic T-cell lines, B-cell lines, and null-cell line: a progress report on surface antigen study of fresh lymphatic leukemias in man.

Permanent human hematopoietic cell lines representing T-cell, B-cell and non T/non B (null-cell) leukemia have been established. Comparative analyses were made for their phenotype characteristics. A number of characteristics common within the 7 T-cell lines studied or distinct from other leukemia-type lines were described. Usefulness, validity and limitation of these findings are discussed in connection to the attempt at classification of ALL, CLL and blastic phase of CML. The great majority of CLL were SmIg+-B-cell leukemia and a single case of T-cell CLL was documented. Except 10% as T-cell ALL and a single case of B-cell ALL, the majority of ALL were found to be the non T/non B ALL. Nevertheless, little evidence was suggested from the present study in favor for a notion that the T-cell ALL and the non T/non B ALL are two distinct diseases.

Antigens, Neoplasm

Feeder layer and nutritional requirements for the establishment and cloning of human malignant lymphoma cell lines.

Cell lines were successfully established in continuous suspension culture from 10 patients with a histopathological diagnosis of diffuse histiocytic lymphoma (SU-DHL-1 to SU-DHL-10), two with North American Burkitt's lymphoma (SU-AmB-1 and SU-AmB-2), and one with acute lymphoblastic leukemia (SU-ALL-1). By screening a variety of parameters, including media, sera, effusion fluids, feeder layers, and chemical supplements, the nutritive growth requirements of lymphoma cells obtained from malignant effusions and lymph node biopsies were determined for each tumor. Most of these cell lines initially required human skin fibroblast or epithelial cell feeder layers from which they could be weaned after one to six weeks in culture and maintained in Roswell Park Memorial Institute Tissue Culture Medium 1640 containing 20% fetal calf serum and 10% pooled human serum. Several of these cell lines were successfully cloned on 0.5% Noble agar substrates. In the presence of human serum and selected feeder monolayers, cloning efficiencies increased significantly from less than 1% to 15 to 25%. In addition, the cloning efficiencies of certain cell lines showed a concentration-dependent increase with specific chemical supplements including L-cysteine and dithiothreitol. Placental colony-stimulating factor, nerve growth factor, epithelial growth factor, and fibroblastic growth factor were ineffective in augmenting the cloning efficiencies of the human lymphoma cell lines. After a single passage on agar, cells subpassaged from visible colonies showed markedly increased cloning efficiencies to levels as high as 50%. Such cloning efficiencies, coupled with the use of replica plating, make this technique applicable to genetic and quantitative radiobiological, immunological, and chemotherapeutic studies. Although these methods have thus far been used only with lymphoreticular tumors, they may also be applicable to the cell culture of other human neoplasms and normal tissues.

Burkitt Lymphoma

Search for inhibitors against herpes simplex virus type-I in cell extracts derived from human lymphoblastoid cell lines.

Cell extracts obtained from KB cells and 5 human lymphoblastoid cell lines including 2 from Burkitt's lymphoma (P3HR-1 and Raji), one each from nasopharyngeal carcinoma (no.223), acute lymphatic leukemia (MOLT-4) and a healthy person (NC-37) were tested for their inhibitory effects on the growth of herpes simplex virus type-1 (HSV-1) in green monkey kidney (GMK) cells by the plaque titration method. The relationship between the production of HSV-1 inhibitors and the degree of Epstein-Barr virus (EBV) genome repression in lymphoblastoid cells were also examined. Among the cell lines used P3HR-1 and no.223 cells produced a few EBV particles, Raji and NC-37 cells contained EBV genomes only, and MOLT-4 as well as KB cells were EBV genome-negative. The results revealed that P3HR-1 cell extract showed a tendency to inhibit HSV-1 growth in GMK cells but the other 4 lymphoblastoid cell lines and KB cells did not produce HSV-1 inhibitors, indicating that EBV genomes governing the formation of EBV structural antigens were not related to the production of HSV-1 growth inhibitors. The extracts from MOLT-4 cells, which are only a T lymphocyte cell line used in this study, stimulated HSV-1 growth in GMK cells significantly.

Antiviral Agents

The effect of pH on incorporation of galactose by a normal human cell line and cell lines from patients with defective galactose metabolism.

Incorporation of radioactive galactose into TCA-insoluble material of galactosemic fibroblasts is more sensitive to low pH than is the incorporation by normal human fibroblasts. This study was undertaken to determine (1) whether there was any pH which could correct or counteract the galactosemic defect relative to galactose incorporation, and (2) whether the low pH effect was specific for galactose metabolism or whether general cellular metabolism in galactosemic cells was more sensitive to low pH than that in normal cells. The pH dependencies of incorporation of radioactive galactose and glucose into cellular macromolecules were investigated in galactosemic and normal cells. Normal cells have a biphasic curve with respect to galactose incorporation with peaks at pH 7.0 and 8.5. Galactosemic cells have only the high pH peak. The maximum incorporation by galactosemic cells was never more than about 30% that seen by normal cells under the conditions of these experiments. Thus manipulation of the pH alone cannot correct the galactosemic defect. The rate of incorporation of radioactive galactose was studied in normal, galactosemic and galactokinase deficient cells, at pH 7.2 and at pH 6.3. At pH 7.2, galactosemic cells incorporate galactose at a linear rate which is 30 to 40% that of normal cells while incorporation by kinase-deficient cells is between 5 and 10% of normal. At pH 6.3, the incorporation is also linear. However, galactosemic cells now exhibit the same rate as kinase-deficient cells in which the low level of incorporation is unaffected by pH. These results suggest that incorporation of galactose by galactosemic cells at low pH is not due to metabolic death of the cells, but may be due to the inhibition of some specific step or steps along a metabolic route of galactose metabolism other than the Leloir pathway.

Cell Line

Protocol for the isolation and characterization of extracellular vesicles and particles from human and murine cell lines.

Cells produce a heterogeneous population of extracellular vesicles and particles (EVPs). Small extracellular vesicles (sEVs or exosomes) are lipid membrane-enclosed vesicles with sizes ranging from 30 to 150 nm. Here, we present a protocol to isolate and characterize EVPs from the conditioned medium of cell lines. We describe steps for cell culture, conditioned media collection, differential ultracentrifugation, and EVP characterization. We then detail procedures for proteomic and biodistribution analyses. For complete details on the use and execution of this protocol, please refer to Yeung et al.1.

Animals

Tumour growth and melanogenesis in hamster tumours in vivo and in vitro: growth, cytochemistry and ultrastructure of tissue cultural cell lines.

Cell lines were established from three hamster melanomas. One was a spontaneous melanotic tumour which lost its ability to produce pigment. Two were induced with DMBA (9.10 dimethyl 1,2-benz/a/anthracene). One of these was pigmented. The two amelanotic lines (CHT-1 and 2) produced highly malignant amelanotic tumours after reimplantation of tissue culture cells. Electron microscopy showed that melanin forming organelles were absent. Tyrosinase activity was also absent. The line established from the pigmented tumour (CHT-8) retained its pigment production for the first seven transfers. Cells from these cultures produced slow growing pigmented tumours. Cells from the 7th to the 35th transfer, a period of 28 weeks, failed to produce tumours but cells from the 36th and subsequent transfers produced slow growing amelanotic tumours. The change in tumorigenicity was not related to changes in the growth rate of the cells in vitro: this remained constant after the 11th transfer generation. Tyrosinase activity and a whole range of melanin forming organelles were present in cells of transfers 1 to 7 but absent from subsequent transfers. Type A and H virus particles were present in the two amelanotic cell lines, CHT-1 and 2. Although the two amelanotic lines produced highly malignant tumours the loss of a differentiated character--melanin production--was not invariably associated with increased malignancy. Three cell lines should provide a good system for studying the relationship between tumour differentiation and growth.

Acid Phosphatase

Human cell membrane components bound to beta2-microglobulin in T cell-type cell lines.

Cell membrane components bound to beta2-microglobulin were isolated from Renex 30 (a nonionic detergent)-solubilized membrane materials of two human T cell-type cell lines, MOLT-4 and CCRF-CEM, by gel filtration and lectin affinity chromatography. The isolation was carried out by following the beta2-microglobulin activity by radioimmune inhibition assay. The T cell membrane components bound to beta2-microblogulin had a uniform molecular size of about 200,000 daltons and most of them showed an affinity to lentil lectin. The isolated membrane components were radioiodinated and examined for identity to HLA antigens by sequential precipitation with rabbit anti-HLA antiserum (specific to HLA large components) and with rabbit anti-beta2-microblogulin antiserum. In addition to HLA antigens, the beta2-microglobulin-bound components obtained from the MOLT-4 cells were found to contain certain membrane components that are the same in molecular size as the HLA large components but that are different antigenically from the HLA large components. On the other hand, the beta2-microglobulin-bound membrane components obtained from the CCRF-CEM cells were all HLA antigens. No other membrane components were involved in the binding.

Cell Line

Surface adhesive properties of baboon lymphocyte and derived lymphoblastoid cell lines.

Cell surface adhesiveness of lymphocytes isolated from the peripheral blood of Papio hamadryas monkeys was compared to the adhesiveness of lymphoblastoid cell lines derived by transformation of these lymphocytes with herpesvirus Papio. For the quantitative comparison of the cell surface adhesive properties, a recently developed latex particle adherence assay was utilized. It was found that cell surface adhesiveness of the suspension lines was substantially lower than that of their precursor lymphocytes.

Adhesiveness

Thy-L antigen expression on rat brain cell lines.

Cell lines derived from the central nervous system of rats were screened serologically for the presence of Thy-1 (theta), a cell surface differentiation antigen shared by brain and thymus of rats and mice. Both cytotoxicity absorption and indirect immunofluorescence assays were performed using a rabbit anti-rat thymocyte serum (ATS) with Thy-1 specificity. The complement-dependent cytotoxicity of ATS detected a mouse-rat cross-reacting determinant of the molecule bearing the Thy-1 antigen. Of 20 lines tested, 1 of 6 neuronal and 7 of 14 non-neuronal lines expressed Thy-1, as judged by their capacity to absorb ATS cytotoxicity for a Thy-1 positive thymoma line. Similar results were obtained in quantitative absorption assays of these lines employing a mouse anti-Thy 1.1 alloantiserum, but the xenoantiserum (ATS) was more sensitive for detecting the rat molecule bearing Thy-1. Indirect immunofluorescence, which was performed on several of the lines, yielded results in complete agreement with the cytotoxicity absorption assays, and revealed a generalized distribution of antigen in a speckled or patchy pattern over the membrane of cell bodies and processes.

Animals

Tubuloreticular structures in human lymphoid cell lines. A cell biological study.

Human lymphoid cell lines were studied as an experimental model for the spontaneous or induced occurrence of tuburloreticular structures (TRS). It was possible to induce TRS after culturing the EB-3 cell line with 20 mug/ml bromodeoxyuridine (BrUdR) during 96 h. Starvation, culturing at lower temperature (32 degrees) or inhibition of DNA synthesis did not give rise to the production of TRS. The response to BrUdR could be blocked with 60 mug/ml thymidine but not with 60 mug/ml deoxycytidine. The addition of 5 mug/ml cytarabine or the removal of BrUdR at different times resulted in inhibition of TRS induction, indicating that BrUdR had to be incorporated into DNA during at least 48 h. After incorporation, neither the presence of BrUdR nor DNA synthesis was necessary for the production of TRS. These experiments and the finding that in the cell line IHTC-33, which does not produce Epstein-Barr virus associated antigens, TRS were spontaneously present, exclude a correlation between TRS and these antigens. However, the induction of TRS by BrUdR may be related to the activation of another (latent) virus.

Antigens, Viral

Separation of cells containing R-type virus-like particles from a simian virus 40-induced hamster tumor cell line.

Cells derived from a simian virus 40-induced hamster fibrosarcoma were separated into two distinct cell bands of differing buoyant densities. The lighter cell band or fraction (F1) had a buoyant density range of 1.025-1.032 g/ml and comprised 3.8% of the total cells applied to the gradient, whereas the heavier cell fraction (F2) had a buoyant density range of 1.054-1.074 g/ml and comprised 95.3% of the total cells applied. Both cell fractions were tumorigenic and did not differ greatly in cell type, viability, mitotic index, or their ability to incorporate [3H]thymidine. However, ultrastructurally, the F1 cells contained R-type virus-like particles within dilated intracisternal spaces and exhibited cytoplasmic vacuoles. In the F2 cells, few detectable R-type particles and cytoplasmic vacuoles were revealed by electron microscopy. The F2 cells demonstrated a twofold greater ability to incorporate [14C]protein hydrolysate into proteins than did the F1 cells.

Cell Line

Establishment of an epitheloid cell line and a fusiform cell line from a patient with nasopharyngeal carcinoma.

An epithelioid cell line and a fusiform cell line were established from a tumor biopsy from a patient with nasopharyngeal carcinoma which as histologically diagnosed as a well differentiated squamous cell carcinoma. Based on studies of the cell growth pattern, chromosome analysis, heterotransplantation, and electron microscopy, these two cell lines were considered to be squamous carcinoma cells, and the fusiform cells might have originated from the epithelioid cells. There were many round cells on top of the epithelioid and fusiform cell sheets, many of which became continuously detached into the medium. Cultures initiated from these floating round cells grew into their original epithelioid or fusiform forms. No lymphoblastoid cell line could be established after cultivating these two cell lines for more than one year. No EB virus particle or early antigen could be detected in these two cell lines by means of electron microscopic examination and indirect immunofluorescence test.

Agglutination

Surface charge characteristics of cells from malignant cell lines and normal cell lines of the human hematopoietic system.

Cells from malignant and normal lines of human hematopoietic origin were studied for their surface charge characteristics with the use of the following criteria: 1) the electron microscopic appearance of cell membranes after labeling with cationized ferritin (CF) either before or after glutaraldehyde fixation, 2) electrophoretic mobility, 3) total sialic acid content, and 4) agglutinability with poly-L-lysine (PLL). CF induced a time-dependent redistribution of surface receptors in unfixed malignant cells but not in unfixed normal cells. After 10 seconds of labeling with CF, both normal and malignant unfixed cells showed a uniform and even labeling pattern. After 5 minutes of labeling, malignant cells exhibited a highly pronounced pattern of clusters and patches, as distinct from a random and even pattern exhibited by normal cells. Both normal and malignant cells after fixation exhibited an equivalent random and even labeling pattern with CF, independent of the duration of labeling. The malignant cells studied possessed less sialic acid, had a lower electric mobility, and were agglutinated more readily with PLL than were the normal cells.

B-Lymphocytes

Rejection by syngeneic mice of cell variants obtained by mutagenesis of a malignant teratocarcinoma cell line.

Cells from the malignant teratocarcinoma line PCC4.azal were treated with the mutagen N-methyl-N'-nitro-N-nitrosoguanidine. Fifty-five clones were isolated from the surviving cells. Twelve clones are unable to form tumors in the syngeneic 129/Sv mice. However, these "tum-" clones form tumors as readily as the original cells when they are injected into irradiated mice. Moreover, they stimulate the production of immune memory cells, which protect the injected animals and confer resistance by adoptive transfer. The tum- clones are therefore unable to generate tumors in syngeneic mice because they elicit an immune rejection response.

Animals